AUTHOR=Lin Yazhou , Cong Hui , Liu Kewei , Jiao Yucheng , Yuan Ye , Tang Guoqing , Chen Yong , Zheng Yuehuan , Xiao Jiaqi , Li Changwei , Chen Zhe , Cao Peng 

TITLE=Microbicidal Phagocytosis of Nucleus Pulposus Cells Against Staphylococcus aureus via the TLR2/MAPKs Signaling Pathway

JOURNAL=Frontiers in Immunology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2019.01132

DOI=10.3389/fimmu.2019.01132

ISSN=1664-3224

ABSTRACT=<p>Intervertebral disc (IVD) is an immune-privileged organ that lacks immunocytes, such as macrophages or neutrophils; therefore, it is unclear how IVD immunological defense against bacterial infection occurs. Here, we demonstrated that nucleus pulposus cells (NPCs), the vital machinery for maintaining the homeostasis of IVD, exerted microbicidal activity against <italic>Staphylococcus aureus</italic> via induction of phagolysosome formation. Moreover, we found that the Toll-like receptor 2 (TLR2)/mitogen-activated protein kinases (MAPKs) signaling pathway is critical for bacterial phagocytosis and phagolysosome formation of NPCs. These findings demonstrated for the first time that NPCs could function as non-professional phagocytes against <italic>S. aureus</italic> infection, thereby enhancing antimicrobial defense against bacterial infections in IVDs.</p>